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MyDailyTool

PDF Compress

Reduce PDF file size by recompressing the document structure. No external server — compressed and downloaded directly in your browser.

Drop a PDF here or click to choose

How to use the pdf compress

Drop a PDF and compression happens automatically. Download the result if the file is smaller.

Formula & explanation

pdf-lib re-serialises the PDF with cross-reference object streams (xref streams) enabled — this removes one of the largest sources of byte bloat in older PDF writers.

Examples

A Word-exported PDF that's 4 MB due to unoptimised XRef tables may compress to 1.5 MB this way.

Frequently asked questions

How much will it compress?
Results vary widely. PDFs already using xref streams won't shrink. Best gains come from Word/LibreOffice exports and old PDF writers.
Does it reduce image quality?
No — images are not resampled or recompressed. Only the document structure is optimised.
Are my files uploaded anywhere?
No — all processing runs in your browser.

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